Field of the Invention
The invention relates to a reactor plant for culturing phototropic microorganisms with a reactor vessel and a photosynthetic module with light-intensity control, which are connected with one another in a circulation circuit by a pump and are controllable via a control unit.
The invention furthermore relates to a process for culturing phototropic microorganisms in a culture medium, in which process the culture medium together with the microorganisms is pumped, by means of a pump, in a circulation circuit from a reactor vessel through a photosynthetic module, the delivery rate of the pump being regulatable as a function of at least one reference quantity.
Description of the Related Art
DE 296 07 285 U1 discloses a reactor plant for culturing phototropic microorganisms where a reactor vessel and a photosynthetic module are connected with one another in a circulation circuit via a pump. A culture medium with the phototropic microorganisms to be cultured is circulated via pipelines of the circulation circuit. The pump in this system is controllable via a control unit which is connected to sensors for measuring the temperature, pH values, the oxygen partial pressure and the optical density. A bypass conveys the culture medium to a separation segment arranged within the reactor vessel, by which segment the biomass can be separated off.
The disadvantage of the prior art known plant and the process which it entails is that the fermentation must be terminated when the media constituents, or the substrate, have been consumed and when the desired biomass concentration in the separation segment has been achieved.
Furthermore, EP 0 968 273 B1 discloses a plant for the production of phototropic organisms and cell cultures with exposure to light by photochemical and photocatalytic reactions and photoinducible processes, where a reactor vessel and a photosynthetic module which are connected with one another in a circulation circuit by a pump and are controllable via a control unit. At a certain dry-matter concentration in the culture medium, the biomass is harvested. To this end, the culture suspension is conveyed to a harvesting device with the aid of the system pump. The harvesting device consists of a harvesting container, a harvesting pump, a separator and a biomass container. The separator separates the biomass from the liquid medium, which can be recirculated into the reactor vessel.
Moreover, DE 198 14 253 C2 discloses a plant and a method for the production of biomass by means of photosynthesis. Again, a reactor vessel and a photosynthetic module are connected with one another in a circulation circuit by a pump. The culture medium together with the microorganisms is pumped, by the pump, from the reactor vessel into the photosynthetic module, which is designed as a plate module, and travels back into the reactor vessel via a return pipe and a scrubber. Upon reaching a certain dry-matter concentration, the culture medium, or the biomass, are conveyed to a harvesting device with the aid of the pump. Here, the harvesting device consists of an intermediate reservoir, a delivery pump and a centrifuge. The centrifuge separates the biomass from the liquid medium, which is conveyed back into the reactor. The resulting biomass is conveyed to a processing device.
Again, the fermentation must be ended here when the media constituents have been consumed and the desired biomass concentration has been reached.
The object of the present invention is therefore to improve the existing plants and to obtain a prolonged fermentation time, which leads to a higher space-time yield. Also, it is intended to make possible, or improve, the separating off of extracellular products.